The Toggle-Recoil chiropractic procedure for cervical adjustment involves applying manual force abruptly to a cervical vertebrae, most commonly to the first vertebrae, which is known as the atlas, in a manner such that the head of a patient is snapped to one side and then allowed to recoil. Heretofore, this procedure has often been performed with the aid of devices developed by Joseph Clay Thompson such as those shown in U.S. Pat. Nos. 2,684,064, 2,727,510, 2,791,215, 2,886,029 and 3,343,531. Another prior art device designed for this use in cervical adjustment is that of Dr. Orville L. Puckett which is shown in U.S. Pat. No. 3,111,944.
Basically, the just mentioned devices have included a headrest that may be forced downwardly against a spring counterforce until a stop is encountered. Once the stop is struck a limited degree of recoil is inherently developed by the internal resilience of the body itself. Since the degree of such recoil is dependent upon the degree of body resiliency of the particular patient in whom it occurs, chiropractors must prejudge such body resiliency to determine the amount of force to be applied manually in order to produce the desired magnitude of recoil force. This, however, has proven to be difficult to do in a reliable and predictable manner. A hazard and limitation has also existed with regard to their use with patients of relatively rigid cervical structure who cannot tolerate substantial applications of force without risk of injury. Accordingly, the present invention is directed at providing a chiropractic adjustment device for use in practicing the Toggle-Recoil procedure which overcomes limitation and problems associated with those of the prior art.